Pipe cutter



J. T. ELLIS PIPE CUTTER Sept. 24, 1940.

Filed May 26, 1956 2 Sheets-Sheet 1 sept. 24, 1940. J T. ELLIS 2,215,638

PIPE CUTTER Patented Sept. 24, 1940 STATES 12 Claims.

This invention relates in general to a pipe cutter, and particularly to that type of pipe cutter designed for use inside of a well or the like into which the pipe has been lowered, whereit is desired to sever one portion of the pipe from another without removing the same from the well.

Various pipe cutters have been designed in the past for the purpose of cutting pipe under the conditions just referred to, but various diiculties have been encountered from time to time such as for instance the fact that in the prior art devices it has been possible to expand the cutting blades of the pipe cutter when the pipe was not in position within a section of pipe. It has also been found that in various of the prior art constructions there is a tendency for the blades to become expanded or partially so when there is no desire on the part of the operator for the blades to be in expanded position, and that due to this fact it is not an infrequent occurrence for the blades to become partially expanded when not in position with the inner pipe and when the end of a section of pipe is encountered to be damaged thereby.

It is an object of this invention to provide a pipe cutter which may be easily operated and positively controlled at all times, and in which the blades cannot be accidentally or unintentionally expanded when the device is not in place within a section of pipe.

It is a further object to provide a device of the type set forth which may be operated by iluid pressure exerted downwardly within the drill stern upon which the cutter is mounted, and to provide in such a structure a means which will prevent the actuation of the cutter blades by such hydraulic pressure and permit of a circulation of iiuid under pressure without expansion of the blades during such time as the cutter is not within a section of pipe.

It is a further object of this invention to provide an anchoring means for anchoring and accurately positioning the cutter within the Vpipe during the time that a cut is being made.

With the above and other objects in view, this invention consists of the various parts and combinations thereof illustrated in the accompanying drawings and set forth in the following description, it being understood, however, that the disclosure of said drawings and description is by way of example and illustration only, and is not to be taken as in any way a limitation upon the scope of this invention. Such limitation is to be only by the prior art, and by the terms of the 55 appended claims.

Referring now to the drawings in which like out I Fig. 1 is a vertical sectional view illustrating p a portion of a 'cutter mechanism constructed in 5 ,accordance with this invention anchored in position within a'pipe to be cut.

Fig. 2 is a similar view of the lower portion of the device illustrated in Fig. 1, the illustration of Fig. 2 being a continuationof the lower portion of Fig. 1.v l A Fig. 3 is a horizontal cross section taken along the line 3,-3 of Fig. '1.

Fig. 4 is a yhorizontal cross section taken along the line i4-4 of Fig. 1.

Fig. 5 is a horizontal cross section taken along the line 5-5 of Fig. 1.

Fig. 6 is a horizontal cross section taken along the line 6--6 of Fig. 2. v

Fig. 7 is a view illustrating a portion of the mechanism illustrated in Fig. 1, parts thereof being shown in cross section, along a vertical plane at right angles to that of Fig. 1, and the cutter mechanism being shown as itis being inserted into the end of a section yof pipe.

Fig. 8 isa view illustratinga continuation of the lower portion of Fig. '7.

Fig. 9 is a vertical lcross section of a slightly modified form of the 'actuating mechanism at the upper end of the cutter assembly.

Fig. 10 is a View illustrating the entire cutter assembly in elevation as it is being lowered into a section of pipe.

Referring now more in detailto the device illustrated in the drawings, the numeral l illustrates a pipe section within which it is desired to locate the cutter for the purpose of severing a portion thereof. The numeral 2 illustrates a cylindrical or tubular member the inner portion of which is of cylindrical form, and is rfinished, smoothly as illustrated at3. The lower end of this tubular member 2 is internally threaded to receive the upper end of the frame of the block member il. Within this member is a chamber 5 which may be of cylindrical or other suitable shape, but which is preferably of somewhat smaller diameter than the chamber 3 within the tubingv 2. The member 4, which may be termed a support for the cutter blades, is vprovided with oppositely disposed slots 6 within which are mounted the levers or arms 8 carrying the cutter blades 9 at their lower ends. T'he arms 8 are pivotally mounted within the slots 6 by'rneans such as the pins i0, and the cutter blades are secured within sockets in the arms 8 by means such as set screws II.

Threadedly secured onto the lower end of the support 4 is a small hollow shaft or tubing section I2 which extends downwardly therefrom. This section is provided with a central bore I3 and is threaded at its lower end onto a shoe or pilot member I4. The pilot member I4 likewise has a bore I5 extending therethrough, and on its lower surface is beveled or formed with a conical shape as at I6 to provide for the guidance of the mechanism into the well.

Surrounding the hollow shaft I2 between the support 4 and the member I4 is a sleeve II slidably mounted thereon and having a hollow interior I8 which ts around the hollow shaft I2. In the lower end portion of this sleeve I1 there are formed substantially vertical slots I9 having oifset portions 28 therein, and having hooks or catches 2I formed in vertical alignment with the off-set portions 20. 'Ihe tubular member I2 is provided with elongated lugs 22 projecting from its opposite sides, and adapted to slide upwardly within the slots I3 when the occasion therefor arises. It will be seen that if the sleeve I'I is lowered with respect to the tube I2, the lugs 22 will enter the slots I9 and will be deected into the olf-set portions 28. Thereafter, when the sleeve is moved directly upwardly the lugs 22 will be caught upon the hooks or catches 2l so that the sleeve will be prevented from further upward movement with respect to the tube I2.

Formed in opposite sides of the sleeve I'I there are also formed cavities or seats 23 adapted to slidingly receive the slip members 24. These slip members 24 are normally resiliently pressed in a radially outward direction by means of springs 25 secured by screws 26 to the rear surface of the slips. The slips themselves are prevented from excessive outward movement by means of the screws 27 which serve also as guides for these slips. These particular slips are provided with vertical teeth so that when the device is within a pipe these slips will be pressed into engagement therewith, and will serve to resist rotational movement of the sleeve I'I. It is preferable also that the springs 25 be of sumcient strength so that the engagement between the slips 24 and the walls of the pipe I will be such as to support the weight of the sleeve I'I.

Also formed in opposite sides of the sleeve I7 there are a pair of openings adapted to receive slips 29, the teeth 30 of such slips extending horizontally and being so disposed as to resist downward movement of the sleeve I'I within the pipe. These slips are held in place by screws 3I and 32 positioned at their lower and upper ends respectively, and arranged to permit a limited radial movement of the slips. The openings within which these slips are positioned extend through the sleeve I'I and the inner surfaces of the slips are tapered as at 33 to receive the tapered or frusto conical sleeve 34 which surrounds the upper portion of the tube I2. This sleeve rests upon a small circumferential shoulder or other stop on the tube I2, and is in contact at its upper end with the bearing race 35. The other race 36 of this bearing bears against the lower end of the support 4, and between the two races there are positioned anti-friction ball bearings 31 or the like, The sleeve 34 is adapted to rotate freely upon the tube I2.

Positioned within the chamber 5 of the support 4 and vertically slidable therein is a mandrel 38 having oppositely disposed frusto conical surfaces thereon, such surfaces being adapted to contact with the points 39 and 4S upon the arms 8 to positively position these arms with respect to the support 4 according to the desires of the operator. Surrounding an intermediate portion of the mandrel 38 is a groove 4I for a purpose which will be presently set forth.

The mandrel 38 is carried by a hollow shaft 42, an enlargement 43 being provided thereon, such enlargement being of a size to fit within the chamber 5. Supported on the upper surface of this enlargement 43 are washers 44 of a diameter greater than the chamber 5, but sufliciently small to fit within the chamber 3. Upon this washer 44 and surrounding the upper portion of the stem 42 is a. sleeve 45, this sleeve being in turn surrounded by a compression spring 46, the upper end of which bears against a washer 4l surrounding and suitably secured to the stem 42. Positioned on the upper surface of the washer 4l is a cup-shaped packing 48 held in place by a washer member 49 and a nut 58, the nut 53 being screwed onto a threaded portion on the upper end of the stem 42.

The block 4 in addition to the openings or slots 6 is provided with an additional slot 5I adapted to receive a pawl 52 which is pivoted on a pin 53. 'Ihis pawl is normally pressed into the position shown in Fig. 7 by means of a spring 54, the lower end of the pawl projecting from the surface of the support 4 in this position. 'I'he outer surface of this lower end of the pawl is rounded as at 55, and is adapted to contact the interior of the pipe. The upper end is provided with a sharp inner corner 56 adapted to cooperate with the shoulder or groove 4I upon the mandrel 38 so that when the two are in engagement, the mandrel will be prevented from downward movement.

In the operation of the form just described, the device is first lowered into the well with the mandrel held inits upper position by means of the pawl 52, and with the sleeve Il maintained in its lower position on the tube I2 by virtue of the contact of the lugs 22 within the hooks 2|. In this position the slips 29 are held in a downward position away from the tapered bushing 34, and are thus allowed to move away from the inner wall of the pipe when the pipe is encountered so as to permit downward movement of the device. Prior to the time that the pipe is reached, if it is desired to circulate for the purpose of washing out bridged over portions of the well, or for any other purpose, the uid may be forced downwardly through the drill stem into the chamber 2, and thence downwardly through the hollow shaft 42 and the mandrel 38, and on through the hollow shaft I2 and the shoe I4. The mandrel cannot be moved downwardly during this circulation, because of the fact that it is held in its upper position by contact with the pawl 52.

When a section of pipe is reached, the slips 24 will enter the pipe, followed by the support 4 and the cutter proper, and the outer surface 55 of the pawl 52 will contact with the pipe wall, thus causing the pawl 52 to be moved to such a position that it will not interfere with the downward movement of the mandrel 38. When the point is reached where a cut is to be made, the device is raised slightly, and the drill stem is rotated to the right, after which the device is again lowered. When the drill stem is thus rotated to the right, it rotates the tube I2, and because of the contact of the slips 24 with the interior of the pipe I, the

sleeve Il will be held stationary so that such downward movement of the tube I2 will move the lugs 22 downwardly through the slots I9, and will move the rotatable bushing or mandrel 34 into contact with the inner surfaces of the slips 29,

thus forcing these slips outwardly into contact with the pipe walls and limiting any further downward movement of the cutter mechanism. Fluid may then be forced into the drill stem and because of the fact that the mandrel 38 is no longer held in its upper position, such fluid will force the mandrel downwardly against the pressure of the spring 46, and will cause its frusto conical surface to cooperate with the points 39 and 40 on the arms 9 to move these arms in such a direction as to expand the cutter blades and move the cutters 9 into contact with the walls of the pipe. The drill stem may then be rotated with continuous pressure applied to the fluid in the drill stem, and the cutters will operate to cut off the section of pipe.

After the cutting operation is completed, the device may be raised so as to move the bushing 34 upwardly with respect to the slips 29, thus permitting the slips to move inwardly and disengage the pipe wall. On this upward movement the lugs22 will enter the slots I9 as before, and be deected into the olf-set portion 20 of these slots. The slips 29 being released, the entire device may then be removed from the hole, or if desired, downward movement of the drill stem will cause the lugs 22 to again engage the catches 2|, and the entire device may be moved downwardly to a new location where the pipe l may again be severed.

Referring to Fig. 9 of the drawings, a modified form illustrated involves the replacement of the cylindrical member 2 with la member 51. This member 51 likewise has a cylindrical chamber therein which is adapted to receive the nut 58 which in this form holds the washer 4l in place. However, at its upper end, the member 51 is formed with a. restricted portion 59 through which passes the relatively small extension 50 of the member 6|. It will be noted that the small portion 50 of the member 6I is of considerably greater length than the restricted portion 59 of the member 5l', so that the member 6I is permitted an appreciable sliding movement with respect to the member 5l. The lower end of the portion 60 is provided with a head 62 which may be in the form of a nut screwed thereon, or any other suitable arrangement. Formed in the opposite sides of the portions 60 and 59 are key ways adapted to receive the keys 63. These keys, as will be readily apparent, prevent relative rotary motion of the member 6I and the member 57, while permitting a relative longitudinal motion of these members. The member 6I is hollow, and is adapted to receive the drill stem 64 at its upper end.

In operation, this latter form is exactly the same as that illustrated in the other figures of the drawings, with the exception that the mandrel is operated by lowering the drill stem after the slips have been locked into place in the manner previously described. This lowering of the drill stem, as will be readily apparent, lowers the head 62 of the member 6l, and causes it to move the head 58 on the mandrel stem 42 in a downward direction. This movement has exactly the same eifect as the movement caused by pumping downwardly through the drill stem in the form previously described.

i It will be understood that various changes may bemade in the details of construction set forth herein without departing from the. spirit or scope of lthis invention as dened in the appended claims.

It will be apparent furthermore that there has.

been set forth and provided by this invention a device capable of carrying out fully all of the objects thereof.

I-Iaving described my invention, I claim:

1. In a pipe cutter, a cutter body, cutter blades mounted within said body for outward movement with respect thereto, means longitudinally movable with respect to said cutter body for moving said cutter blades into operative position, and a latch for normally latching said means against longitudinal movement in a direction to move the cutter blades into operative position, said latch including a part adapted to release said latch upon insertion of said cutter body into an opening of less than a predetermined diameter.

2. In a pipe cutter, a cutter body, cutter blades mounted within said body for outward movement with respect thereto, means longitudinally movable with respect to said cutter body for moving said cutter blades into and out of operative position, and a latch for normally latching said means when the same is in position to hold said cutter blades out of operative position, said latch including a part adapted to release said latch upon insertion of said cutter body into an opening of less than a predetermined diameter.

3. In a pipe cutter, a cutter body, cutter blades mounted within said body for outward movement with respect thereto, means longitudinally movable with respect to said cutter body for moving said cutter blades into and out of operative position, spring means for normally holding said longitudinally movable means in position to maintain said cutter blades out of operative position, and a latch operative when said body is not within an opening of less than a predetermined diameter tolatch said longitudinally movable means in the position to which it is urged by said spring means, said latch including a part adapted torelease said latchupon insertion of said cutter body into an opening of less than said predetermined diameter. y

4. In a pipe cutter, a cutter body, cutter blades mounted within said body for outward movement with respect thereto, Ymeans longitudinally movable with respect to said cutter body for moving l said cutter blades into and out of operative position, spring means for normally urging said longitudinally movable means toward the position for maintaining said cutter blades in inoperative position, said longitudinally movable means having a shoulder thereon, and a pawl having a part adapted to engage said shoulder to maintain said longitudinally movable means in the position to which it is urged by said spring, said pawl including a part projecting from said cutter body and adapted to contact with the wall of an opening to release said pawl from said shoulder when said cutter body is inserted into an opening of less than a predetermined diameter.

5. In a pipe cutter, a cutter body, cutter blades mounted within said body for outward movement with respect thereto, means longitduinally movable with respect to said cutter body for moving said cutter blades into and out of operative position, said longitudinally movable means including a part adapted to be actuated by hydraulic pressure exerted downwardly thereupon to move said blades to operative position, and a latch for normally latching said longitudinally movable means against such movement, said latch including a part adapted to release said latch upon insertion of said cutter body into an opening of less than a predetermined diameter.

6. In a pipe cutter, a cutter body, cutter blades mounted within said body for outward movement with respect thereto, means longitudinally movable with respect to said cutter body for moving the said cutter blades into and out of operative position, means for supporting said cutter body and having a telescoping joint therein adapted upon telescoping action to cause longitudinal movement of said longitudinally movable means for expanding said cutter blades into operative position, and a latch for normally latching said longitudinally movable means against such movement, said latch including a part adapted to release said latch upon insertion of said cutter body into an opening of less than a predetermined diameter.

, 7. In a pipe cutter, a cutter body, cutter blades mounted within said body for outward movement with respect thereto, a reduced extension on said body, a lug on said reduced extension, a sleeve slidably mounted on said extension and having a bayonet slot therein adapted to cooperate with said lug to releasably hold said sleeve against upward movement on (said extension, spring pressed gripping means carried by said sleeve and adapted to continuously engage a pipe within which the cutter is located; other gripping means carried by said sleeve and having a part extending through the wall thereof to a point adjacent the outside of said reduced extension, a frusto conical mandrel rotatably mounted and held from longitudinal sliding movement on said extension adjacent its upper end, said mandrel having its larger end uppermost, whereby when the cutter is within a pipe and said lug is released from said slot, downward movement of said cutter body will cause said mandrel to positively expand said other gripping means to anchor the cutter body against downward movement, and means to actuate said cutter blades.

8. In a pipe cutter, a cutter body, cutter blades mounted within said body for outward movement with respect thereto, a reduced extension on said body, a lug on said reduced extension, a sleeve slidably mounted on said extension and having a bayonet slot therein adapted to cooperate with said lug to releasably hold said sleeve against upward movement on said extension, the lower end of said sleeve being shaped to guide said lug into said bayonet slot when said extension is moved upwardly with respect to said sleeve, spring pressed gripping means carried by said sleeve and adapted to continuously engage a pipe within which the cutter is located, other gripping means carried by said sleeve and having a part extending through the wall thereof to a point adjacent the outside of said reduced extension, a frusto conical mandrel rotatably mounted and held from longitudinal sliding movement on said extension adjacent its upper end, said mandrel having its larger end uppermost whereby when the cutter is within a pipe and said lug isl released from said slot, downward movement of said cutter body will cause said mandrel to positively expand said other gripping means to anchor the cutter body against downward movement, and means to actuate said cutter blades.

9. In a pipe cutter, a cutter body, cutter blades included within said body for outward movement with respect thereto, a reduced extension on said body, a lug on said reduced extension, a sleeve slidably mounted on said extension and having a bayonet slot therein adapted to cooperate with said lug to releasably hold said sleeve against upward movement on said extension, said bayonet slot being shaped to guide said lug into latching position with respect thereto when said cutter body is raised, spring pressed gripping means carried by said sleeve and adapted to continuously engage a pipe within which the cutter is located, other gripping means carried by said sleeve and having a part extending through the wall thereof to a point adjacent the outside of said reduced extension, a frusto conical mandrel rotatably mounted and held from longitudinal sliding movement on said extension adjacent its upper end, said mandrel having its larger end uppermost, whereby when the cutter is within a pipe and said lug is released from said slot, downward movement of said cutter body Will cause said mandrel to positively expand said other gripping means to anchor the cutter body against downward movement, and whereby upon upward movement of said cutter body said other gripping means will be released and said sleeve will be latched against upward movement with respect to said extension so that the cutter may be lowered to a lower position within the well, and means to actuate said cutter blades.

10. In a pipe cutter, a cutter body, cutter blades mounted within said body for actuating movement with respect thereto, a reduced extension on said body, a lug on said reduced extension, a sleeve slidably mounted on said extension and having a bayonet slot therein adapted to cooperate with said lug to releasably hold said sleeve against upward movement on said extension, spring pressed gripping means carried by said sleeve and adapted to continuously engage a pipe within which the cutter is located, other gripping means carried by said sleeve and having a part extending through the wall thereof to a point adjacent to the outside of said reduced extension, a tapered mandrel rotatably mounted and held from longitudinal sliding movement on said extension adjacent its upper end, said mandrel having its llarger end uppermost, whereby when the cutter is within a pipe and said lug is released from said slot, the downward movement of said cutter body causes said mandrel to positively expand said other gripping means to anchor the cutter body against downward movement and means to actuate said cutter blades.

1l. In a pipe cutter, a cutter body, cutter blades carried by said body for actuating movement with respect thereto, an extension on said body, means slidably mounted on said extension and having a bayonet slot connection therewith adapted to` releasably hold said means against upward movement on said extension, resiliently pressed gripping means carried by said sleeve and adapted to continually engage a pipe within which the cutter is located, other gripping means carried by said sleeve and having a part extending to a point adjacent to said extension; a tapered mandrel mounted on and held from longitudinal sliding movement on said extension, said mandrel having its larger end uppermost, whereby when thecutter is within a pipe and said bayonet slot connection is released, downward movement of said cutter body causes said mandrel to expand said other gripping means to anchor the cutter body against downward movement, and means to actuate said cutter blades.

12. In combination, a cutter body, a tubular member adapted to extend into a well from the Surface of the ground for suspending said body and supplying uid under pressure thereto, a portion of said body extending below said cutter blades, anchoring means on said body below said cutter blades, having downwardly directed teethv and movable to anchor said body against downward movement, and means exposed to the interior of said tubular member and adapted to be operated by iluid pressure therein for actuatn ing said blades to cutting position when .said body is so anchored.

JAMES T. ELLIS 

